I have a few questions on my sunset platy. I got two of them about 1 week ago and I think they are two females from what I have read, but one has a black dot on it and some forums say that is a sign that it is gravid. It is also larger than the other one and has been swimming normaly, but yesterday I found it just laying on the bottom quite often. Can someone tell me if it is gravid or you if you need anymore info please just ask.